Wire-gripping part of electric terminal member



y 1963 H. w BATCHELLER 3,696,136

WIRE-GRIFFING PART OF ELECTRIC TERMINAL MEMBER Original Filed Oct. 31,1957 United States Patent 3,696,136 WIRE-GRIPPING PART OF ELECTRICTERMINAL MEIR/BER Hugh W. Batcheller, Newton, Mass., assignor to KentMfg. Corp, Newton, Mass, a corporation of Massachusetts Originalapplication Oct. 31, 1957, Ser. No. 693,712. Dr-

vided and this application Dec. 31, 1958, Ser. No.

1 Claim. (Cl. 339-276) This application is divided from my copendingapplication, Serial No. 693,712., filed October 31, 1957, now Patent No.2,982,329. The invention relates to an electric terminal member havingimproved means for attaching it to a wire. Electric terminals such, forexample, as connector members are attached to the ends of Wires prior totheir being put to use. There are various ways of attaching a metalmember to the end of a wire but the most frequently used [form ofconnection is made by crimping a tongue or tongues of metal around thebared end portion of an insulated wire. If this is properly done, aconnection can be had which is as good electrically as a connection madeby soldering or welding the wire to the metal piece.

Some electric connector members are made to be attached to wires whichare laid at right angles to the longitudinal axis of the connectormember. In such cases, a tongue is provided which extends in thedirection of the axis of the member, such tongue being adapted to bewrapped or crimped around the end portion of wire to make the joint orconnection between the metal member and the wire. When such a tongue iscrimped or curled about a wire, the metal retains a tendency to unrollor relax somewhat, no matter how much force is exerted in the crimpingoperation. This tendency to relax is often augmented by temperatureconditions when current which is passing through the wire and terminalmember heats up the joint between them. It is an object of the presentinvention to make the joint secure so that the tongue which is crimpedaround the wire cannot relax so as to ease the pressure of the crimpedtongue on the wire itself. Such pressure between the metal member andthe wire which it embraces is important for a good electrical connection.

According to the invention, the tongue which is crimped around a Wire issecured in place by means of a small 111g or tab which is struck up fromthe standing part of the tongue in such a way as to overlap theextremity of the tongue after the latter has been Wrapped around thewire. For a more complete understanding of the invention reference maybe had to the following description thereof and to the drawing of which:

FIGURE 1 is a perspective view of an electric terminal member attachedto the end of an insulated wire;

FIGURE 2 is a perspective view of the terminal member before beingattached to a wire;

FIGURE 3 is a plan view of the same;

FIGURE 4 is a section on the line 44 of FIGURE 3;

FIGURE 5 is a perspective view of a terminal member similar to thatshown in FIGURE 2 except that both of the wire-embracing tongues arelongitudinally corrugated; 5 FIGURE 6 is a section on the line 6-6 ofFIGURE and FIGURE 7 is a sectional view of a terminal member which hasbeen crimped to a wire.

While the invention relates to joints between any sheet metal member anda wire, a connector member 20 which is adapted to be attached to a wiredisposed at right angles to its longitudinal axis is illustrated on thedrawing by way of example since the problem of making a tight electricalconnection between a terminal member of this kind and a wire has beenfound to be particularly troublesome, but the invention is not limitedto any particular type of terminal member. As shown in FIGURE 2 themember 20 has a tongue 22 which is adapted to be crimped to a bared endof a wire 24 which is insulated as at 26. The tongue 22 is an integralextension of the floor of the connector member 20 and projects from theterminal portion of the member along the longitudinal axis thereof. Inorder to facilitate the crimping operation, the end portion 28 of thetongue 22 is bent upward as indicated in FIGURE 2 forming an angle 30 toreceive a wire 24. If desired, the tongue 22 may be provided with alongitudinal indentation resulting in a rib 32 on the other face thereofto stifien the tongue so that when it has been crimped around a wire ashereinafter described, the rib 32 Will help to oppose the tendency onthe part of the tongue to relax slightly its grip on the wire 24.According to the present invention, however, a more positive means isprovided for anchoring the tongue in its crimped position and preventingany relaxing or loosening thereof. To this end a tab or lug 34 is struckup from the standing portion of the tongue 22, that is, the portionwhich is adjacent to the terminal part of the member 20. The lug isformed by a U-shaped cut and is struck up from the plane of the standingportion of the tongue 22 so that it assumes a vertical position. When aconnector member 20 is to be attached to the bared end of a wire, theWire is laid in the angle 30 and the end portion 28 of the tongue iscrimped around the wire by suitable dies until its extremity touches thefloor of the tongue 22 and bears against the lug 34. The lug is thenbent down to overlap the end portion 28 of the tongue and to press downon it. The lug 34 may be pressed down with sufificient force to pressthe mid portion of the extremity of the tongue slightly downward intothe hole 50 from which the lug 40 was struck. Since the lug 34 isrelatively short and therefore stiff, it firmly holds the extremity ofthe tongue down against the standing part of the tongue so that itcannot relax to ease the pressure of the tongue on the wire which itembraces.

Ordinarily, a second tongue 52 is provided to embrace the portion of theinsulated wire which is adjacent to the bared end. This tongue isparallel to and longer than the tongue 22 since it has to embrace anelement of greater diameter, this element including the insulation aswell as the wire itself. This tongue may be provided with a locking tabif desired but ordinarily it will not be required since the strength ofthe grip of the crimped tongue 52 on the insulated portion of the wireis not so important as the strength of the grip of the tongue 22 on thewire itself, the latter forming the joint through which the electriccurrent flows.

Instead of the stifiening rib 32 extending along the median of thetongue 22, one or both of the tongues may be longitudinally corrugatedas indicated at 60 and 62 m FIGURES 5 and 6. Such corrugations serve tocounter- 3 act to' a considerable extent the natural tendency on thepart of crimped tongues to relax a little when the crimping pressurethereon is relieved.

It will be evident that there are modifications and changes that may bemade in the specific embodiments herein shown and described Withoutdeparting from the spirit or scope of the invention as set forth in thefollowing claim.

I claim:

An electric terminal member made of a single piece of sheet metal andcomprising a terminal portion and a portion adapted to grip a wire, saidWire-gripping portion comprising a longitudinal extension from theterminal portion and having an extremity, a part of said extension beingbent up forming an angle in which a wire can be laid, said extensionhaving a small locking lug struck up therefrom and adapted to be engagedby the end of said extension when it is orimped around a wire and to bebent to overlap the extremity of the cramped extension.

References Cited in the file of this patent UNITED STATES PATENTS2,596,528 Carlson May 13, 1952 2,659,871 Berg Nov. 17, 1953 2,716,741Ustin Aug. 30, 1955 2,845,108 Hammell et a1 July 29, 1958 2,884,478Becker et' a1. Apr. 28, 1959 2,945,206 Ham-mell July 12, 1 960

